Cam shaft drive arrangement for internal combustion engines



Dec. 28, 1965 BINDER 3,225,610

CAM SHAFT DRIVE ARRANGEMENT FOR INTERNAL COMBUSTION ENGINES Filed 061:. 9, 1963 81/ 9%, Law

United States Patent s 225 610 CAM SHAFT naive XRGEMENT non INTERVAL coMnUsrroN ENGINES Robert Binder, Stuttgart-Zuifeuhausen, Germany, assignor The present invention relates to an internal combustion engine with a cam shaft driven from the crank shaft preferably by means of a gear train or reduction gear, which cam shaft is held in the axial direction within the crankcase and serves, inter alia, for the drive of auxiliary units or aggregates, for example, of a fuel supply pump.

With the prior art constructions of this type the cam shaft is held in the axial direction by means of a bolt supported at a fixed housing part which engages into a bore provided at the end face of the cam shaft and by means of a compression spring arranged within the bore. In order to avoid these multi-partite axial securing arrangements and especially to dispense with the bore provided in the end face of the cam shaft, it has already been proposed heretofore for internal combustion engines with a crankcase divided in the longitudinal direction to secure the cam shaft by means of a collar which engages between annular grooves of the crankcase halves. While this type of securing of the cam shaft avoids separate special securing elements, it entails, however, the disadvantage that the seat of the cam shaft changes under the influence of thermal expansions of the crankcase.

According to the present invention these disadvantages are avoided in that the axial securing of the cam shaft takes place by a spring-loaded driving member of the auxiliary aggregate which is supported against a control surface arranged at the end face of the cam shaft, which control surface serves for purposes of drive of the auxiliary aggregate. By the use of such an arrangement, separate structural parts serving for the axial securing of the cam shaft may be dispensed with whereby simultaneously a unilateral or one-sided mounting support thereof is assured so that the thermal expansions of the crankcase have no influence on the position of the cam shaft. A favorable arrangement with good accessibility results from an arrangement in which the control surface operatively associated with the spring-loaded driving member is arranged on the drive gear or pinion of the cam shaft. Preferably the drive gear is operatively connected with a flange-disk of the cam shaft which, for purposes of the axial securing, is provided on the side opposite the control surface with an abutment surface that abuts against a wall of the crankcase. The control surface is advantageously accommodated on a form-body connected with the drive gear against which is supported the driving member of the auxiliary aggregate arranged at an acute angle to the cam shaft axis. A simplification in the manufacture is achieved according to the present invention in that the form-body is constituted by an inclined disk consisting of a pressed-out sheet metal part, the diameter of which corresponds to the diameter of the annular flange of the cam shaft and is fitted into the driving gear wheel on the side thereof opposite the side of the annular flange.

Accordingly, it is an object of the present invention to provide a cam shaft drive arrangement for internal combustion engines of the type described hereinabove which eliminates the aforementioned shortcomings and disadvantages encountered with the prior art constructions by simple and expedient means.

It is another object of the present invention to pro- 3,225,516 Patented Dec. 28, 1965 vide a drive arrangement for the cam shaft of an internal combustion engine which is not only simple in construction but is also held securely in the axial direction without the use of numerous parts and without the presence of bores within some of the parts.

A still further object of the present invention resides in the provision of a drive arrangement for the cam shaft of an internal combustion engine which assures a secure support in the axial direction without the danger of changes in the position of the cam shaft as a result of thermal expansions on the part of housing parts.

A still further object of the present invention resides in the provision of an axial securing arrangement for the drive means of the cam shaft of an internal combustion engine which is extremely simple, obviates the need for separate structural parts and utilizes the drive of an auxiliary aggregate for realizing the axial securing.

Still another object of the present invention resides in the provision of a drive arrangement for the cam shaft of an internal combustion engine which in combination with the advantages enumerated hereinabove is easily accessible, may be manufactured and assembled in a simple and relatively inexpensive manner and assures a completely satisfactory and reliable operation.

These and other objects, features and advantages of the present invention will become more obvious from the following description when taken in connection with the accompanying drawing which shows, for purposes of illustration only, in the single figure thereof, a drive arrangement for the cam shaft of an internal combustion engine from the crank shaft thereof in accordance with the present invention.

Referring now to the drawing which shows in the single figure thereof, a longitudinal cross sectional view through the control drive of an internal combustion engine, reference numeral 1 designates therein the crankcase of an internal combustion engine which is divided in the longitudinal center plane. A crank shaft 2 is supported within the crankcase 1 in a conventional manner. A cam shaft 3 provided with inlet and outlet cams 4 and 5 for the valve actuating mechanisms (not shown) is supported within the crankcase 1 at a distance and axially parallelly to the crank shaft 2. A gear train or reduction gear 8 is provided, for purposes of driving the cam shaft 3, within a space 7 separated by a partition Wall 6 fromthe remainder crankcase 1, which gear train 8 is operatively connected with the crank shaft 2. The drive gear or pinion 9 for the cam shaft 3 is provided with an aperture 10 on the side thereof facing the partition wall 6 into which is fitted a flange-disk 11 made in one piece with the cam shaft 3. The flange-disk 11 is provided with an abutment surface 12 which abuts against a projection 13 of the partition wall 6. The partition wall 6 is provided with an aperture 14 for receiving therein the cam shaft 3. An inclined disk 15 provided with a control surface 16 and consisting of a stamped-out sheet metal part is arranged at the gear 9 on the side opposite the flangedisk 11. The inclined disk 15 has the same diameter as the flange-disk 11 and is secured at the gear 9 within a recess 18 together with the flange-disk 11 by means of circumferentially distributed rivets 17. The inclined disk 15 serves for purposes of driving a fuel supply pump 19 which is secured at the closure wall 20 of the crankcase 1 disposed at the end face thereof. The pump 19 is provided, in a manner known per se, for purposes of supplying the fuel with a plunger 21 which is held under the influence of a coil spring 22 against the control surface 16 of the inclined disk 15. The abutment surface 12 of the flange-disk 11 is simultaneously held by the pressure of the spring 22 against the projection 13 of the partition 6 wall 6 and therewith the position and location of the cam shaft 3 is secured in the axial direction.

While I have shown and described one embodiment in accordance with the present invention, it is understood that the same is not limited thereto but is susceptible of numerous changes and modifications as known to a person skilled in the art. Thus, for example, the control surface serving for the auxiliary drive and the axial securing may be made in one piece with the drive gear or pinion of the cam shaft. Furthermore, the control surface for the auxiliary drive may also be accommodated at an end face of the cam shaft whereas the opposite end face of the cam shaft serves for driving the cam shaft. Of course, instead of a fuel supply pump, other auxiliary aggregates, such as an eccentric piston pump or the like may also be driven by the cam shaft.

Thus, it is obvious that the present invention is susceptible of numerous changes and modifications, and I there- 'fore do not wish to be limited to the details shown and described herein but intend to cover all such changes and modifications as are encompassed by the scope of the appended claims.

I claim:

1. An internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former, the drive means for driving said auxiliary unit including a spring-loaded driving member, and said cam shaft being provided with control surface means at one end face thereof,

and securing means for securing said cam shaft in the axial direction, said securing means including said spring-loaded driving member which is supported in contact with said control surface means.

2. An internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former including two meshing gears, one of said gears being operatively con nected with said crankshaft for rotation in unison therewith and the other being operatively connected with said cam shaft for rotation in unison therewith, the drive means for driving said auxiliary unit including a springloaded driving member, and said cam shaft being provided with control surface means at one end face thereof,

and securing means for securing said cam shaft in the axial direction, said securing means including said spring-loaded driving member which is supported in contact with said control surface means, said control surface means being arranged at the gear operatively connected with said cam shaft.

3. An internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former including two meshing gears, one of said gears being operatively connected with said crank shaft for rotation in unison therewith and the other being operatively connected with said cam shaft for rotation in unison therewith, the drive means for driving said auxiliary unit including a springloaded driving member, and said cam shaft being provided with control surface means at one end face thereof, and securing means for securing said cam shaft in the axial direction, said securing means including said springloaded driving member which is supported in contact with said control surface means,

said control surface means being arranged at the gear operatively connected with said cam shaft,

said cam shaft being provided with a flange-disk and said other gear being operatively connected with said flange-disk, said flange disk being provided on the side opposite said control surface means with an abutment surface which abuts against a wall portion of the crankcase for axially securing said cam shaft.

4. An internal combustion engine provided with a crankcase supporting therein a crankshaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former including two meshing gears, one of said gears being operatively connected with said crank shaft for rotation in unison therewith and the other being operatively connected with said cam shaft for rotation in unison therewith, the drive means for driving said auxiliary unit including a springloaded driving member, and said cam shaft being provided with control surface means at one end face thereof,

and securing means for securing said cam shaft in the axial direction, said securing means including said spring-loaded driving member which is sup ported in contact with said control surface means, said control surface means being arranged at the gear operatively connected with said cam shaft,

said cam shaft being provided with a flange-disk and said other gear being operatively connected with said flange-disk, said flange disk being provided on the side opposite said control surface means with an abutment surface which abuts against a wall portion of the crankcase for axially securing said cam shaft,

said control surface means being provided on a form body connected with said other gear, said driving member forming an acute angle to the cam shaft axis and resting against said form body.

5. An internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former including two meshing gears, one of said gears being operatively connected with said crank shaft for rotation in unison therewith and the other being operatively connected with said cam shaft for rotation in unison therewith, the drive means for driving said auxiliary unit including a springloaded driving member, and said cam shaft being pro vided with control surface means at one end face thereof,

and securing means for securing said cam shaft in the axial direction, said securing means including said spring-loaded driving member which is supported in contact with said control surface means, said control surface means being arranged at the gear operatively connected with said cam shaft,

said cam shaft being provided with a flange-disk and said other gear being operatively connected with said flange-disk, said flange disk being provided on the side opposite said control surface means with an abutment surface which abuts against a wall portion of the crankcase for axially securing said cam shaft,

said control surface means being provided on a form body connected with said other gear, said driving member forming an acute angle to the cam shaft axis and resting against said form body,

and said form body being constituted by an inclined disk member consisting of a sheet metal stamping, the diameter of said inclined disk member corresponding to the diameter of said annular flangedisk and being fitted into said other gear on the side opposite said flange-disk.

6. An internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former including two meshing gears, one of said gears being operatively connected with said crank shaft for rotation in unison therewith and the other being operatively connected with said cam shaft for rotation in unison therewith, the drive means for driving said auxiliary unit including a spring-loaded driving member, and said cam shaft being provided with control surface means at one end face thereof,

and securing means for securing said cam shaft in the axial direction, said securing means including said spring-loaded driving member which is supported in contact with said control surface means,

said control surface means being arranged at the gear operatively connected with said cam shaft,

said control surface means being provided on a form body connected with said other gear, said driving member forming an acute angle to the cam shaft axis and resting against said form body.

7. An internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft held in said crankcase in the axial direction and serving as drive means for an auxiliary unit, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former including two meshing gears, one of said gears being operatively connected with said crank shaft for rotation in unison therewith and the other being operatively connected with said cam shaft for rotation in unison therewith, the drive means for driving said auxiliary unit including a spring-loaded driving member, and said cam shaft being provided with control surface means at one end face thereof,

and securing means for securing said cam shaft in the axial direction, said securing means including said spring-loaded driving member which is supported in contact with said control surface means,

said control surface means being arranged at the gear operatively connected with said cam shaft,

said control surface means being provided on a form body connected with said other gear, said driving member forming an acute angle to the cam shaft axis and resting against said form body,

and said form body being constituted by an inclined disk member consisting of a sheet metal stamping and being fitted into said other gear.

8. In an internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft, and an auxiliary unit comprising:

means operatively connecting said crank shaft with said cam shaft for driving the latter from the former,

drive means for driving said auxiliary unit including a spring-loaded driving member,

and securing means for securing said cam shaft in the axial direction, said securing means including said driving member and a control surface arranged at one of the end faces of said cam shaft against which surface is supported said driving member. 9. In an internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft, and an auxiliary unit comprising:

gear means operatively connecting said crank shaft with said cam shaft for driving the latter from the former, said gear means including two meshing gears, one of said gears being operatively connected with said crank shaft and the other being operatively connected with said cam shaft, drive means for driving said auxiliary unit including a spring-loaded driving member, and securing means for securing said cam shaft in the axial direction, said securing means including said driving member and a control surface arranged.

at one of the end faces of said cam shaft against which surface is supported said driving member,

said control surface being arranged at the gear operatively connected with said cam shaft,

said cam shaft being provided with a flange-disk operatively connected with said last-mentioned gear, said flange-disk being provided with an abutment surface on the side opposite said control surface which abuts against a wall of the crankcase for axially securing said cam shaft,

said control surface being provided on a form body connected with said last-mentioned gear, said driving member forming an acute angle to the cam shaft axis and resting against said form body,

said form body being constituted by an inclined disk member consisting of a sheet metal stamping, the diameter of said inclined disk corresponding to the diameter of said annular flange disk and being fitted into said last-mentioned gear on the side opposite said flange disk.

10. In an internal combustion engine provided with a crankcase supporting therein a crank shaft, a cam shaft, and an auxiliary unit having a spring-loaded driving member, and means operatively connecting said crank shaft with said cam shaft for driving the latter from the former,

the improvement essentially consisting of securing means for securing said cam shaft in the axial direction, said securing means including said driving member and a control surface arranged at one of the end faces of said cam shaft against which surface is supported said driving member.

References Cited by the Examiner UNITED STATES PATENTS BROUGHTON G. DURHAM, Primary Examiner. 

1. AN INTERNAL COMBUSTION ENGINE PROVIDED WITH A CRANKCASE SUPPORTING THEREIN A CRANK SHAFT, A CAM SHAFT HELD IN SAID CRANKCASE IN THE AXIAL DIRECTION AND SERVING AS DRIVE MEANS FOR AN AUXILIARY UNIT, AND MEANS OPERATIVELY CONNECTING SAID CRANK SHAFT WITH SAID CAM SHAFT FOR DRIVING THE LATTER FROM THE FORMER, THE DRIVE MEANS FOR DRIVING SAID AUXILIARY UNIT INCLUDING A SPRING-LOADED DRIVING MEMBER, AND SAID CAM SHAFT BEING PROVIDED WITH CONTROL SURFACE MEANS AT ONE END FACE THEREOF, AND SECURING MEANS FOR SECURING SAID CAM SHAFT IN THE AXIAL DIRECTION, SAID SECURING MEANS INCLUDING SAID SPRING-LOADED DRIVING MEMBER WHICH IS SUPPORTED IN CONTACT WITH SAID CONTROL SURFACE MEANS. 